To Convert or Not Convert? that is the question!

[EdBray]

After getting a Tokina AT-X 300mm f2.8 SD and wanting to try a bit of wildlife photography (not done any before), so I purchased a couple of converters to increase the focal length.

I bought a pair of Kenko Teleplus PRO 300 DG converters (1.4x & 2x) as Tokina state that these converters were designed specifically for this lens, and the best thing is that no aperture information is given allowing full use of the f2.8 focus point and also allows focussing on my 5DMk2 at f8

I tried them on the lens to give a 300 f2.8, 420 f4, 600 f5.6 & 840 f8 all shots were taken at maximum aperture and at ISO 400 on my 5DMk2. Metering and focussing were taken from the roof tiles. Focussing slows slightly with the converters attached, but is not as bad as was expected. The roof was about 120 yards away.

I will accept that the results are not going to be as good as a prime lens on its own, but who can afford a 600mm f5.6 & 840mm f8 primes for occasional use?

300mm f2.8

300mm f2.8 100% crop

300mm + 1.4x Converter (giving 420mm @ f4)

300mm + 2x Converter (giving 600mm @ f5.6)

300mm + 1.4x and 2x Converters stacked (giving 840mm @ f8)

300mm + 1.4x and 2x Converters stacked (giving 840mm @ f8) 100% crop

 

[CT]

I can't see any problem with you using these converters Ed. As you say they're for occasional use and the results will always look their worst when viewed at 100%. Viewed at web size or for smaller prints, it looks like you'll get more than acceptable results.

 

[Andysnap]

Have to say Ed they're pretty impressive. Leaning toward the Tokina myself now.

Andy

 

[EdBray]

I'm really pleased with the results, okay I admit that the 840mm shot is nothing like as sharp as the 300mm shot which is bourne out by the 100% crops, but there is not too much loss of contrast from any of the converted shots and as an emergency measure to get that bit closer it does the job nicely. And these shots were all taken wide open, if the occasion allowed stopping down I would suspect they would be a little better again.

Strangely enough, I found that the lens seemed to handle better with the 1.4x on as 420mm f4.

I can't wait to go out and try some wildlife stuff now!